Electric transaxle with integral power generating device

ABSTRACT

A vehicle drive and control system includes an input shaft driven by a prime mover and extending into a housing to drive a generator. An electric motor powered by the generator drives an output axle, which may be a single axle extending out one side of the housing, or a through shaft extending through the electric motor and out both sides of the housing. The input shaft may be parallel to the axle. A generator controller is configured to back-drive the generator when certain predetermined conditions are met. A motor controller may control an output of the motor based on input received via an operator control device, and the motor controller is configured to operate the motor as a generator under certain operating conditions. The transaxle includes a common housing in which the power generator, the motor, and controllers for the generator and electric motor are disposed.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of U.S. patent applicationSer. No. 14/838,626, filed on Aug. 28, 2015, now U.S. Pat. No.9,828,025, which claims the benefit of Provisional App. No. 62/043,274,filed Aug. 28, 2014, and Provisional App. No. 62/048,518, filed Sep. 10,2014. This application also claims priority from Provisional App. No.62/357,789 filed Jul. 1, 2016. The terms of all of these priorapplications are incorporated herein by reference in their entirety.

BACKGROUND OF THE INVENTION

This invention relates to a drive system for use in vehicles such aslawn and garden tractors, stand-on mowers, walk-behind snow throwers andmowers, and the like, including both single transaxle drives and dualtransaxle drives for use in zero-turn applications.

SUMMARY OF THE INVENTION

The invention comprises a transaxle having an electric motor that iscontrolled by a vehicle user and that drives at least one output axle.The transaxle includes a power generating device that powers theelectric motor and a reduction gear train engaged to and driven by theelectric motor. The transaxle includes a common housing in which thepower generator, the electric motor, and the reduction gear system areeach disposed. In dual-axle systems, the transaxle also includes adifferential engaged to and driven by the reduction gear system to powera pair of oppositely extending output axles. The differential is alsodisposed within the common housing.

In further embodiments, a U-shaped or Z-shaped arrangement is used,wherein an input shaft of the generator, which is directly connected toand is driven by a prime mover, through, e.g., a belt and pulley system,is parallel to the output shaft of the electric motor. This arrangementprovides for a more compact unit. In further embodiments, a motorcontroller, or a pair of motor controllers, and a generator controller,may be enclosed in a common housing with the generator and electricdrive motor(s).

A better understanding of the invention will be obtained from thefollowing detailed descriptions and accompanying drawings, which setforth illustrative embodiments indicative of the various ways in whichthe principals of the invention may be employed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic drawing of one embodiment of the transaxle of thepresent disclosure including a power generating device, an electricmotor, a reduction gear train, and a differential all disposed within acommon housing.

FIG. 2 is a schematic drawing of another embodiment of the transaxle ofthe present disclosure including a power generating device, an electricmotor, and a reduction gear train all disposed within a common housing.

FIG. 3 is a schematic drawing of one embodiment of the transaxle of thepresent disclosure including a power generating device, two electricmotors, and two reduction gear trains all disposed within a commonhousing.

FIG. 4 is a top plan view of a riding vehicle including the transaxle ofFIG. 1 and a mechanical steering mechanism.

FIG. 5 is a top plan view of a riding vehicle including the transaxle ofFIG. 1 and electronically-controlled steering.

FIG. 6 is a top plan view of a riding zero-turn vehicle including two ofthe transaxles as shown in FIG. 2.

FIG. 7 is a top plan view of a stand-on zero turn vehicle including thetransaxle of FIG. 3.

FIG. 8 is a top plan view of a walk-behind zero-turn vehicle includingthe transaxle of FIG. 3.

FIG. 9 is a top plan view of riding zero-turn vehicle similar to thatshown in FIG. 6 and including two of the transaxles shown in FIG. 2,with the prime mover driving the deck assembly.

FIG. 10 is a schematic drawing of a further embodiment of the transaxleof the present disclosure including a power generating device and twoelectric motors disposed within a common housing, wherein the outputshaft of each electric motor is directly driving respective drivewheels.

FIG. 10A is a schematic drawing of an embodiment similar to that shownin FIG. 10, with details of an alternative control apparatus shown.

FIG. 11 is a schematic drawing of a further embodiment of the transaxleof the present disclosure including a power generating device and anelectric motor in a U-shaped or Z-shaped arrangement and disposed withina common housing with a reduction gear train.

FIG. 12 is a schematic drawing of a further embodiment of the transaxleof the present disclosure including a power generating device and anelectric motor in a Z-shaped arrangement and disposed within a commonhousing, where an output shaft of the electric motor is directly drivinga drive wheel.

FIG. 13 is a schematic drawing of a further embodiment of the transaxleof the present disclosure including a power generating device and anelectric motor disposed within a common housing, where an output shaftof the electric motor consists of a through shaft to directly drive twoseparate drive wheels.

FIG. 14 is top plan view of a zero-turn vehicle incorporating thetransaxle depicted in FIG. 10A.

DETAILED DESCRIPTION OF THE DRAWINGS

The description that follows describes, illustrates and exemplifies oneor more embodiments of the invention in accordance with its principles.This description is not provided to limit the invention to theembodiment(s) described herein, but rather to explain and teach theprinciples of the invention in order to enable one of ordinary skill inthe art to understand these principles and, with that understanding, beable to apply them to practice not only the embodiment(s) describedherein, but also any other embodiment that may come to mind inaccordance with these principles. The scope of the invention is intendedto cover all such embodiments that may fall within the scope of theappended claims, either literally or under the doctrine of equivalents.

It should be noted that in the description and drawings, like orsubstantially similar elements may be labeled with the same referencenumerals. However, sometimes these elements may be labeled withdiffering numbers or serial numbers in cases where such labelingfacilitates a more clear description. Additionally, the drawings setforth herein are not necessarily drawn to scale, and in some instancesproportions may have been exaggerated to more clearly depict certainfeatures. As stated above, this specification is intended to be taken asa whole and interpreted in accordance with the principles of theinvention as taught herein and understood by one of ordinary skill inthe art.

Referring now to the Figures, FIG. 1 illustrates one embodiment of atransaxle 110 including a power generating device 120, an electric motor130, a reduction gear train 140, and a differential 142 all disposedwithin a common transaxle housing 112. The power generating device 120is powered by an input shaft 114 connected to and driven by a primemover, such as prime mover 491 in FIG. 4. Power generating device 120and the other power generating devices depicted herein are shown asgenerators, although it will be understood that each may alternativelybe an alternator or any other suitable device, depending on the enduser's needs. The prime mover may also power other outputs, such as amowing deck or an auger (not shown) for a snow thrower. It will beunderstood that the power generating devices depicted herein, such aspower generating device 120, may use or incorporate a separatecontroller for purposes of power management.

The power generating device 120 converts the rotation of input shaft 114into electrical power. Electrical power generated by power generatingdevice 120 is transferred from power generating device 120 to electricmotor 130 via conductor 122 (such as suitable wiring) to power electricmotor 130, and to a battery such as battery 475 shown in FIG. 4, bymeans of conductor 124. Using this electrical power, electric motor 130drives a motor output shaft 134 that is engaged to and drives thereduction gear train 140. The reduction gear train 140 is engaged todifferential 142, and provides the desired reduction from the motoroutput shaft 134 to differential 142. The differential 142 is engaged toand individually controls the output of (i.e., the rotation of) a firstaxle 144 a and an opposing second axle 144 b, each of which extends fromthe common transaxle housing 112. The first axle 144 a is engaged to afirst wheel 193 a configured to rotate therewith, and second axle 144 bis engaged to an opposing second wheel 193 b configured to rotatetherewith.

One or more motor controls can be powered by the power generating device120 or by a battery, or a combination of the two, and can be used toprovide a control signal to electric motor 130 via conductor 132 (suchas suitable wiring) to permit a vehicle user to control the electricmotor 130.

FIG. 2 illustrates another embodiment of a transaxle 210 including apower generating device 220, an electric motor 230, and a reduction geartrain 240 all disposed within a common transaxle housing 212. A pair oftransaxles 210 may be employed, for instance, in a vehicle havingzero-turn capabilities, such as vehicle 690 shown in FIG. 6. The powergenerating device 220 is powered by an input shaft 214 connected to anddriven by a prime mover. The prime mover may also power other outputs,such as a mowing deck or an auger (not shown) for a snow thrower.

The power generating device 220 converts the rotation of input shaft 214into electrical power. Electrical power generated by power generatingdevice 220 is transferred from power generating device 220 to electricmotor 230 via conductor 222 to power electric motor 230, and to abattery such as battery 675 shown in FIG. 6, by means of conductor 224.Using this electrical power, the electric motor 230 drives a motoroutput shaft 234 that is engaged to and drives the reduction gear train240. The reduction gear train 240 is engaged to and drives an axle 244,and provides the desired reduction from motor output shaft 234 to axle244. The axle 244 is engaged to a wheel 293 configured to rotatetherewith.

One or more motor controls can be powered by the power generating device220 or by a battery, or a combination of the two, and can be used toprovide a control signal to electric motor 230 via conductor 232 (suchas suitable wiring) to permit a vehicle user to control the electricmotor 230.

FIG. 3 illustrates another embodiment of a transaxle 310 including apower generating device 320, a first electric motor 330 a, a secondelectric motor 330 b, a first reduction gear train 340 a, and a secondreduction gear train 340 b all disposed within a common transaxlehousing 312. The transaxle 310 may be employed, for instance, in awalk-behind mower or snow-thrower. The power generating device 320 ispowered by input shaft 314 connected to and driven by a prime mover. Theprime mover may also power other outputs, such as a mowing deck or anauger (not shown) for a snow thrower.

The power generating device 320 converts the rotation of input shaft 314into electrical power. Electrical power generated by power generatingdevice 320 is transferred from power generating device 320 to firstelectric motor 330 a via a first conductor 322 a to power electric motor330 a. Electrical power generated by power generating device 320 is alsotransferred to second electric motor 330 b via a second conductor 322 bto power the second electric motor 330 b, and to a battery such asbattery 775 shown in FIG. 7, by means of conductor 324. Using thiselectrical power, first electric motor 330 a drives a first motor outputshaft 334 a that is engaged to and drives first reduction gear train 340a and second electric motor 330 b drives a second motor output shaft 334b that is engaged to and drives second reduction gear train 340 b. Thefirst reduction gear train 340 a is engaged to and drives a first axle344 a, and provides the desired reduction from first motor output shaft334 a to first axle 344 a. The first axle 344 a is engaged to a firstwheel 393 a configured to rotate therewith. Similarly, second reductiongear train 340 b is engaged to and drives a second axle 344 b, andprovides the desired reduction from second motor output shaft 334 b tosecond axle 344 b. The second axle 344 b is engaged to a second wheel393 b configured to rotate therewith.

One or more motor controls can be powered by the power generating device320 or by a battery, or a combination of the two, and can be used toprovide control signals to first electric motor 330 a and secondelectric motor 330 b via conductors 332 a, 332 b, respectively to permita vehicle user to control the electric motors 330 a, 330 b.

FIGS. 10-13 illustrate further embodiments of this disclosure, todemonstrate the flexibility provided by the compact unit disclosedherein. In FIG. 10, transaxle 1310 includes a power generating device320, a first electric motor 330 a and a second electric motor 330 b, alldisposed within a common housing 312. The power generating devicesdisclosed in the various embodiments may be generators, and forconvenience are sometimes referred to as such; the controls may bereferred to as generator controls for simplicity. In these embodimentsin FIGS. 10-13, the housings such as housing 312 may be referred to astransaxle housings or simply as housings.

Certain components of transaxle 1310 may be identical or substantiallysimilar to those components shown in earlier embodiments using commonnumerals, with minor variations that will be understood by one ofordinary skill in the art. For example, electric motors 330 a, 330 b aremodified from the previously described embodiment in that they aredirectly driving output axles 344 a, 344 b, and other components requiredifferent wiring connections and the like, and the transaxle housing 312will be modified accordingly to accommodate the changes describedherein.

Power generating device 320 is powered by input shaft 314 connected toand driven by a prime mover, wherein input shaft 314 is perpendicular tothe output axles 344 a, 344 b driven by electric motors 330 a, 330 b. Agenerator controller 347 is also disposed inside transaxle housing 312and controls generator loading and therefore power produced. Forexample, should the generator controller 347 detect that the voltage ofbattery 375 is higher than a predetermined threshold (e.g., 12V, 36V or48V depending on the specific system) and/or battery 375 is approachinga full charge, generator controller 347 can start to back-drive thepower generating device 320 and therefore dissipate power. Generatorcontroller 347 can monitor system voltage to determine when to produceelectricity to power the electric motors 330 a, 330 b. Generatorcontroller 347 can be set up to constantly detect and/or calculate thecharge of battery 375 to vary the output of power generating device 320to maintain the desired charge of battery 375. The various batteriesdescribed herein, such as battery 375, can be of similar or identicalconstruction and are typical for use in applications such as thevehicles shown herein. Generator controller 347 may be connected topower generating device 320 by means of conductor 351. It will beunderstood by one of skill in the art that the term “conductor” as usedherein may refer to several conductors (e.g. a wiring harness,electrical cable or grouping of conductors serving a singular function).

In FIG. 10, as in prior embodiments, power generating device 320converts the rotation of input shaft 314 into electrical power.Electrical power generated by power generating device 320 is transferredvia a first conductor 322 a to power first electric motor 330 a.Electrical power generated by power generating device 320 is alsotransferred via a second conductor 322 b to power the second electricmotor 330 b, and to battery 375 by means of conductor 324. Using thiselectrical power, first electric motor 330 a drives a first output axle344 a that is engaged to and drives first wheel 393 a and secondelectric motor 330 b drives a second motor output axle 344 b that isengaged to and drives second wheel 393 b.

A pair of motor controllers 349 a, 349 b can be disposed insidetransaxle housing 312 and connected to respective electric motors 330 a,330 b using conductors 332 a, 332 b. These motor controllers 349 a, 349b are connected to respective operator control devices 384 a, 384 b bymeans of conductors 333 a, 333 b, and can be used to control the speedand direction of electric motors 330 a, 330 b, as well as control suchfactors as top speed, forward and reverse speed and acceleration, andvarious safety features. Operator control devices 384 a, 384 b aredepicted in this embodiment as control levers and may incorporateposition sensor modules as described in connection with otherembodiments. For purposes of this disclosure, speed control mechanismsor “operator control devices” 384 a, 384 b, and the like may include anyor all of the speed control mechanisms, features and functionalitydescribed in U.S. patent application Ser. No. 15/377,706, filed Dec. 13,2016, which is incorporated by reference herein in its entirety.

It will be understood that the pair of motor controllers 349 a, 349 bcould be replaced with a single motor controller such as motorcontroller 349′ shown as an alternative embodiment in FIG. 10, andseparately connected to each electric motor 330 a, 330 b by conductors332 a′ and 332 b′.

By way of example, motor controllers 349 a, 349 b can be programmed toprovide a relatively slow initial acceleration, and can detect wheelslippage (e.g., on wet turf). By combining the motor controllers 349 a,349 b and the generator controller 347 inside transaxle housing 312, amore compact unit is provided. Motor controllers 349 a, 349 b can alsooperate the electric motors 330 a, 330 b to act as generators to slow orstop the vehicle.

Motor controllers 349 a, 349 b can additionally receive inputs fromother sensors, including but not limited to vehicle slope sensors.Should a vehicle slope sensor detect an excessive slope of the vehicle,motor controllers 349 a, 349 b can either stop the electric motors 330a, 330 b or alternately reverse the electric motors 330 a, 330 b to backthe vehicle away from the excessive slope. As can be appreciated, theuse of motor controllers 349 a, 349 b can provide almost instantaneousfeedback with regard to operator input and sensor inputs. It will beunderstood that the generator controllers and motor controllers shown inFIGS. 10-13 can be connected to operator control devices and sensors ona vehicle such as those shown in later figures by means of standardwiring (not shown). It will further be understood that the motorcontrollers and generator controllers shown in other embodiments,including FIGS. 11-13, can operate in a manner similar to that describedabove.

FIG. 10A illustrates an embodiment similar to that shown in FIG. 10, butalso depicting the transaxle 1310′ connected to a CAN-Bus 360 that isconnected to a Vehicle Integration Module (VIM) 355 for providingcontrol of the components of transaxle 1310′. VIM 355 is connected toCAN-Bus 360 by means of a conductor 323 and to battery 375 by means of aconductor 325. CAN-Bus 360 may be connected to motor controllers 349 a,349 b by means of conductors 333 a′, 333 b′ and to generator controller347 by means of conductor 348. Operator controls 384 a′ and 384 b′,which may be similar to those described for FIG. 10, and comprisingposition sensor modules, may also be connected to CAN-Bus 360 by meansof conductors 385 a and 385 b. More details on such a CAN-Bus and VIMsystem can be found in commonly owned application Ser. No. 15/640,300filed on the same date herewith, now U.S. Pat. No. 10,058,031, the termsof which are incorporated herein by reference in their entirety. A PTO(power take off) clutch-brake assembly 350 is also provided in thisembodiment integrally formed with or attached to power generating device320 for connecting a vehicle prime mover to a mowing deck or otherpowered implement via power generating device 320 as is shown in FIG.14.

FIG. 11 illustrates a further embodiment of this disclosure, wheretransaxle 1210 includes a power generating device 220, an electric motor230, and a reduction gear train 240 all disposed within a commontransaxle housing 212. A pair of transaxles 1210 may be employed, forinstance, in a vehicle having zero-turn capabilities, such as vehicle690 shown in FIG. 6. The power generating device 220 is powered by aninput shaft 214 connected to and driven by a prime mover, and in thisembodiment, input shaft 214 is mounted parallel to output shaft 234 andaxle 244, and on the same side of transaxle housing 212 as output axle244. The components of the embodiment of FIG. 11 may be identical orsubstantially similar to the components having common numerals as shownin, e.g., FIG. 2, with modifications that will be understood by a personof ordinary skill in the art. For example, different wiring connectionswill be required, and transaxle housing 212 will be modified toaccommodate the different arrangement of components.

The power generating device 220 converts the rotation of input shaft 214into electrical power. Electrical power generated by power generatingdevice 220 is transferred from power generating device 220 to electricmotor 230 via conductor 222 to power electric motor 230, and to battery275 by means of conductor 224. Electric motor 230 drives a motor outputshaft 234 that is engaged to and drives the reduction gear train 240.The reduction gear train 240 is engaged to and drives an axle 244, andprovides the desired reduction from motor output shaft 234 to axle 244.The axle 244 is engaged to a wheel 293 configured to rotate therewith.It will also be understood that with some additional modifications oftransaxle housing 212, power generating device 220 could be aligned intransaxle housing 212 such that the input shaft extends out the oppositeside of transaxle housing 212 (i.e., on the opposite side of thetransaxle housing 212 from which 244 extends), as shown by alternativeinput shaft 214′.

A motor controller 249 may be placed inside transaxle housing 212 andcan be powered by the power generating device 220 or by battery 275, ora combination of the two, and can be used to provide a control signal toelectric motor 230 via conductor 232 (such as suitable wiring) to permita vehicle user to control the electric motor 230, by means of anoperator control device such as control lever 284 connected thereto byconductor 233. Similarly, generator controller 247 is disposed insidetransaxle housing 212 and connected to power generating device 220 byconductor 251; generator controller 247 operates in a manner similar tothat described for generator controller 347 in FIG. 10, includingproviding the ability to back-drive the power generating device 220 asrequired when, for example, battery 275 is reaching a full charge.Similarly, motor controller 249 can also operate electric motor 230 toact as a generator to slow or stop the vehicle.

FIG. 12 illustrates a further embodiment of this disclosure, wheretransaxle 2210 includes a power generating device 220 and an electricmotor 230 disposed within a common transaxle housing 212, but without areduction gear train. The power generating device 220 is powered by aninput shaft 214 connected to and driven by a prime mover. In thisembodiment, input shaft 214 is mounted parallel to output axle 244, butextending from transaxle housing 212 on the opposite side from outputaxle 244. Again, as noted above, it will be understood that transaxlehousing 212 and other components such as electric motor 230 will bemodified to accommodate the changes described herein.

The power generating device 220 converts the rotation of input shaft 214into electrical power, which is transferred to electric motor 230 viaconductor 222 to power electric motor 230, and to battery 275 by meansof conductor 224. Electric motor 230 drives a motor output axle 244 thatis engaged to and directly drives wheel 293. Electric motor 230 andmotor controller 249 can be powered by the power generating device 220or by battery 275, or a combination of the two, and motor controller 249can be used to provide a control signal to electric motor 230 viaconductor 232 (such as suitable wiring) to permit a vehicle user tocontrol the electric motor 230 by means of an operator control devicesuch as control lever 284 connected thereto by conductor 233.

As before, generator controller 247 is disposed inside transaxle housing212 and connected to power generating device 220 by conductor 251;generator controller 247 operates in a manner similar to that describedfor generator controller 347 in FIG. 10, including providing the abilityto back-drive the power generating device 220 as required when, forexample, battery 275 is reaching a full charge. Similarly, motorcontroller 249 can also operate electric motor 230 to act as a generatorto slow or stop the vehicle.

FIG. 13 illustrates a further embodiment of this disclosure, wheretransaxle 3210 includes a power generating device 220 and an electricmotor 230′ disposed within a common transaxle housing 212. In thisembodiment, motor output axle 244′ consists of a through shaft extendingout both sides of electric motor 230′ to drive both wheels 293. Such adevice may be used, for example, in a walk behind snow thrower or thelike where differential transaxle output or zero turn operation is notrequired. The power generating device 220 is powered by an input shaft214 connected to and driven by a prime mover, and in this embodiment,input shaft 214 is mounted parallel to motor output axle 244′.

The power generating device 220 converts the rotation of input shaft 214into electrical power. Electrical power generated by power generatingdevice 220 is transferred from power generating device 220 to electricmotor 230′ via conductor 222 to power electric motor 230′, and tobattery 275 by means of conductor 224. Using this electrical power, theelectric motor 230′ drives a motor output axle 244′ that is engaged toand directly drives both wheels 293.

As in prior embodiments, electric motor 230′ and motor controller 249can be powered by the power generating device 220 or by battery 275, ora combination of the two, and motor controller 249 can be used toprovide a control signal to electric motor 230′ via conductor 232 (suchas suitable wiring) to permit a vehicle user to control the electricmotor 230′ by means of an operator control device such as a handcontrolled accelerator (e.g. motorcycle-style twist throttle) or footpedal 272 connected thereto by conductor 273. Generator controller 247is disposed inside transaxle housing 212 and connected to powergenerating device 220 by conductor 251; generator controller 247operates in a manner similar to that described for generator controller347 in FIG. 10, including providing the ability to back drive the powergenerating device 220 as required when, for example, battery 275 isreaching a full charge. Similarly, motor controller 249 can also operateelectric motor 230′ to act as a generator to slow or stop the vehicle.

FIG. 4 illustrates a riding vehicle 490 including the transaxle 110 anda frame 492 that supports the transaxle 110. The vehicle 490 includes aprime mover 491 supported by the frame 492 and configured to drive theinput shaft 114 of the transaxle 110, which in turn powers the powergenerating device 120 of transaxle 110 (as described above inconjunction with FIG. 1). In this embodiment, vehicle 490 includes abelt and pulley assembly 497 that operably connects prime mover 491 toinput shaft 114 of transaxle 110 such that prime mover 491 may driveinput shaft 114, though any other suitable power transfer device orsystem may be employed. Prime mover 491 also powers one or more blades498 a of a mowing deck 498 supported by frame 492 of vehicle 490. Inthis embodiment, vehicle 490 includes a belt and pulley assembly 499that operably connects prime mover 491 to mowing deck 498 such thatprime mover 491 may drive blade(s) 498 a, though any other suitablepower transfer device or system may be employed.

Vehicle 490 also includes a controller 470 operatively connected toelectric motor 130 of transaxle 110 and an accelerator pedal 472 (orother suitable operator control device) operatively connected tocontroller 470. Controller 470 and accelerator pedal 472 enable thevehicle user to control the electric motor 130 of transaxle 110. Morespecifically, in this embodiment, when the vehicle user actuates (orreleases) the accelerator pedal 472, the controller 470 sends anappropriate control input to the electric motor 130 of the transaxle 110to modify the output of the electric motor 130 and, therefore, theoutput of the transaxle 110, accordingly. Controller 470 is powered by abattery 475 powered by power generating device 120, though in otherembodiments, controller 470 is powered by a combination of battery 475and the power generating device 120 or solely by the power generatingdevice 120.

Vehicle 490 also includes rear wheels 493 and front wheels 494. The rearwheels 493 are engaged to and driven by transaxle 110 (as describedabove in conjunction with FIG. 1). The front wheels 494 are engaged to asteering mechanism 482 supported by frame 492. The steering mechanism482 includes a steering wheel 480 and a plurality of mechanical linkageslinking front wheels 494 to steering wheel 480 such that rotating thesteering wheel 480 causes the front wheels 494 to rotate accordingly.

FIG. 5 illustrates a riding vehicle 590 including the transaxle 110 anda frame 592 that supports the transaxle 110. Vehicle 590 includes aprime mover 591 supported by frame 592 and configured to drive inputshaft 114 of transaxle 110, which in turn powers the power generatingdevice 120 of transaxle 110 (as described above in conjunction with FIG.1). In this embodiment, vehicle 590 includes a belt and pulley assembly597 that operably connects prime mover 591 to input shaft 114 oftransaxle 110 such that prime mover 591 may drive input shaft 114,though any other suitable power transfer device or system may beemployed.

Vehicle 590 also includes a controller 570 operatively connected toelectric motor 130 of transaxle 110 and an accelerator pedal 572 (orother suitable operator control device) operatively connected to thecontroller 570. The controller 570 and the accelerator pedal 572 enablethe vehicle user to control electric motor 130 of transaxle 110. Morespecifically, in this embodiment, when the vehicle user actuates (orreleases) the accelerator pedal 572, the controller sends an appropriatecontrol input to the electric motor 130 of transaxle 110 to modify theoutput of the electric motor 130 and, therefore, the output of thetransaxle 110, accordingly. Controller 570 is powered by a battery 575supported by frame 592 and powered by the power generating device 120,though in other embodiments the controller 570 is powered by acombination of battery 575 and the power generating device 120 or solelyby the power generating device 120.

Vehicle 590 also includes rear wheels 593 and front wheels 594. The rearwheels 593 are engaged to and driven by transaxle 110 (as describedabove in conjunction with FIG. 1). Each front wheel 594 is engaged to anelectric actuator 579 which is configured to rotate that particularfront wheel 594 about an appropriate vertical axis to provide steering.The electric actuators 579 are operatively connected to controller 570such that controller 570 may control the electric actuators 579. Vehicle590 includes a steering wheel 580 and a steering position sensor 571operatively connected to steering wheel 580 and controller 570. Inoperation, steering position sensor 571 senses and communicates arotation of the steering wheel 580 to controller 570, which controls theelectric actuators 579 to cause the front wheels 594 to rotate accordingto the rotation of steering wheel 580.

Vehicle 590 also includes a mowing deck 598 supported by frame 592 andone or more auxiliary electric motors 577 operatively connected to andconfigured to rotate one or more blades 598 a of mowing deck 598. Inthis embodiment, the one or more auxiliary electric motors 577 areoperatively connected to controller 570, and the necessary operatorswitches as may be required, such that the vehicle user may controloperation of the one or more electric motors 577 and, therefore,rotation of blade(s) 598 a, using controller 570. In certainembodiments, each blade is operatively connected to a separate electricmotor that is configured to rotate that particular blade. In otherembodiments, the vehicle includes fewer electric motors than it doesblades. In these embodiments, certain of the blades may be directlydriven by the electric motors while other of the blades may be driven bythe electric motors via any suitable power transfer device or systemoperatively connecting the electric motors to the blades.

FIG. 6 illustrates a zero-turn vehicle 690 including two transaxles 210a and 210 b and a frame 692 that supports transaxles 210 a and 210 b.Vehicle 690 includes a prime mover 691 supported by frame 692 andconfigured to drive the input shafts 214 of transaxles 210 a and 210 b,which in turn power the power generating devices 220 of the transaxles210 a and 210 b (as described above in conjunction with FIG. 2). In thisembodiment, vehicle 690 includes a belt and pulley assembly 697 thatoperably connects prime mover 691 to input shafts 214 of transaxles 210a and 210 b such that prime mover 691 may drive input shafts 214, thoughany other suitable power transfer device or system may be employed.

Vehicle 690 also includes two control levers 683 a and 683 b (or othersuitable operator control devices), two position sensors 684 a and 684 boperatively connected to the respective control levers 683 a and 683 bsuch that position sensors 684 a and 684 b may detect the positions ofthe corresponding control levers 683 a and 683 b, and a controller 670operatively connected to position sensors 684 a and 684 b. The controllever 683 a, the position sensor 684 a, and the controller 670 enablethe vehicle user to control the electric motor 230 of transaxle 210 a,and the control lever 683 b, the position sensor 684 b, and thecontroller 670 enable the vehicle user to separately control theelectric motor 230 of transaxle 210 b. More specifically, in thisembodiment, when the vehicle user moves control lever 683 a (or 683 b)to a particular position, position sensor 684 a (or 684 b) communicatesthis position to controller 670, which in turn sends an appropriatecontrol input to electric motor 230 of transaxle 210 a (or 210 b) tomodify the output of the electric motor 230 and, therefore, the outputof transaxle 210 a (or 210 b), accordingly. Controller 670 is powered bya battery 675 which is connected to and powered by the power generatingdevices 220 of transaxles 210 a and 210 b, though in other embodimentsthe controller 670 may be powered by a combination of the battery 675and the power generating devices 220 of transaxles 210 a and 210 b,solely by the power generating devices 220 of the transaxles 210 a and210 b, or by the power generating device 220 of only one of thetransaxles 210 a and 210 b.

Vehicle 690 also includes rear wheels 693 and front casters 695. One ofthe rear wheels 693 is engaged to and driven by transaxle 210 a (asdescribed above in conjunction with FIG. 2) and another one of the rearwheels 693 is engaged to and separately driven by the transaxle 210 b(as described above in conjunction with FIG. 2).

Vehicle 690 also includes a mowing deck 698 supported by frame 692 andone or more auxiliary electric motors 677 operatively connected to andconfigured to rotate one or more blades 698 a of mowing deck 698. Inthis embodiment, the one or more auxiliary electric motors 677 areoperatively connected to controller 670, and the necessary operatorswitches as may be required, such that the vehicle user may controloperation of the one or more electric motors 677 and, therefore,rotation of blade(s) 698 a, using controller 670. In certainembodiments, each blade is operatively connected to a separate electricmotor that is configured to rotate that particular blade. In otherembodiments, the vehicle includes fewer electric motors than it doesblades. In these embodiments, certain of the blades may be directlydriven by the electric motors while other of the blades may be driven bythe electric motors via any suitable power transfer device or systemoperatively connecting the electric motors to the blades.

FIG. 9 illustrates a zero-turn vehicle 990 that is similar in manyrespects to the vehicle 690 described above. Vehicle 990 includes twotransaxles 210 a and 210 b and prime mover 991 supported by frame 992,with prime mover 991 configured to drive the input shafts 214 oftransaxles 210 a and 210 b, which in turn power the power generatingdevices 220 of the transaxles 210 a and 210 b (as described above inconjunction with FIG. 2). Vehicle 990 includes a belt and pulleyassembly 997 that operably connects prime mover 991 to input shafts 214of transaxles 210 a and 210 b.

Vehicle 990 also includes two control levers 983 a and 983 b (or othersuitable operator control devices) and two position sensors 984 a and984 b operatively connected thereto to detect the positions of controllevers 983 a and 983 b, and controller 970 operatively connected toposition sensors 984 a and 984 b. Control lever 983 a, position sensor984 a, and controller 970 enable the vehicle user to control theelectric motor 230 of transaxle 210 a, and control lever 983 b, positionsensor 984 b, and controller 970 enable the vehicle user to separatelycontrol electric motor 230 of transaxle 210 b in a manner similar tothat described above. Controller 970 is powered by battery 975 andpowered by the power generating devices 220 of transaxles 210 a and 210b.

Vehicle 990 also includes rear wheels 993 and front casters 995 similarto the embodiment in FIG. 6. Vehicle 990 further includes a mowing deck998 supported by frame 992. Similar to the embodiment shown in FIG. 8,prime mover 991 also powers one or more blades 998 a of a mowing deck998 by means of a belt and pulley assembly 999 that operably connectsprime mover 991 to mowing deck 998 to drive blade(s) 998 a.

FIG. 7 illustrates a zero-turn vehicle 790 including the transaxle 310and a frame 792 that supports the transaxle 310. The vehicle 790includes a prime mover 791 configured to drive the input shaft 314 ofthe transaxle 310, which in turn powers the power generating device 320of the transaxle 310 (as described above in conjunction with FIG. 3). Inthis embodiment, the vehicle 790 includes a belt and pulley assembly 797that operably connects the prime mover 791 to the input shaft 314 of thetransaxle 310 such that the prime mover 791 may drive the input shaft314, though any other suitable power transfer device or system may beemployed. The prime mover 791 also powers one or more blades 798 a of amowing deck 798 supported by the frame 792 of the vehicle 790. In thisembodiment, the vehicle 790 includes a belt and pulley assembly 799 thatoperably connects the prime mover 791 to the mowing deck 798 such thatthe prime mover 791 may drive the blade(s) 798 a, though any othersuitable power transfer device or system may be employed.

The vehicle 790 also includes two control levers 783 a and 783 b (orother suitable operator control devices) on opposite sides of vehicle790, two position sensors 784 a and 784 b operatively connected to therespective control levers 783 a and 783 b such that the position sensors784 a and 784 b may detect the positions of the corresponding controllevers 783 a and 783 b, and a controller 770 operatively connected tothe position sensors 784 a and 784 b. The control lever 783 a, theposition sensor 784 a, and the controller 770 enable the vehicle user tocontrol the electric motor 330 a of the transaxle 310, and the controllever 783 b, the position sensor 784 b, and the controller 770 enablethe vehicle user to separately control the electric motor 330 b of thetransaxle 310. More specifically, in this embodiment, when the vehicleuser moves the control lever 783 a (or 783 b) to a particular position,the position sensor 784 a (or 784 b) communicates this position to thecontroller 770, which in turn sends an appropriate control input to theelectric motor 330 a (or 330 b) of the transaxle 310 to modify theoutput of the electric motor 330 a (or 330 b) and, therefore, the outputof the transaxle 310, accordingly. The controller 770 is powered by abattery 775 and powered by the power generating device 320 of thetransaxle 310, though in other embodiments the controller 770 is poweredby a combination of the battery 775 and the power generating device 320or solely by the power generating device 320.

Vehicle 790 also includes rear wheels 793 and front casters 795. Therear wheels 793 are engaged to and driven by transaxle 310 (as describedabove in conjunction with FIG. 3). Vehicle 790 also includes an operatorplatform 796 on which the vehicle user may stand when operating thevehicle 790.

FIG. 8 illustrates a walk-behind zero-turn vehicle 890 includingtransaxle 310 and a frame 892 that supports transaxle 310. Vehicle 890includes a prime mover 891 supported by frame 892 and configured todrive input shaft 314 of transaxle 310, which in turn powers powergenerating device 320 of the transaxle 310 (as described above inconjunction with FIG. 3). In this embodiment, vehicle 890 includes abelt and pulley assembly 897 that operably connects prime mover 891 toinput shaft 314 of transaxle 310 such that prime mover 891 may driveinput shaft 314, though any other suitable power transfer device orsystem may be employed. The prime mover 891 also powers one or moreblades 898 a of a mowing deck 898 supported by frame 892 of vehicle 890.In this embodiment, vehicle 890 includes a belt and pulley assembly 899that operably connects prime mover 891 to mowing deck 898 such thatprime mover 891 may drive blade(s) 898 a, though any other suitablepower transfer device or system may be employed.

The vehicle 890 also includes two control levers 883 a and 883 b (orother suitable operator control devices), two position sensors 884 a and884 b operatively connected to the respective control levers 883 a and883 b such that the position sensors 884 a and 884 b may detect thepositions of the corresponding control levers 883 a and 883 b, and acontroller 870 operatively connected to the position sensors 884 a and884 b. The control lever 883 a, the position sensor 884 a, and thecontroller 870 enable the vehicle user to control the electric motor 330a of the transaxle 310, and the control lever 883 b, the position sensor884 b, and the controller 870 enable the vehicle user to separatelycontrol the electric motor 330 b of the transaxle 310. Morespecifically, in this embodiment, when the vehicle user moves thecontrol lever 883 a (or 883 b) to a particular position, the positionsensor 884 a (or 884 b) communicates this position to the controller870, which in turn sends an appropriate control input to the electricmotor 330 a (or 330 b) of transaxle 310 to modify the output of theelectric motor 330 a (or 330 b) and, therefore, the output of thetransaxle 310, accordingly. The controller 870 is powered by a battery875 and powered by the power generating device 320 of the transaxle 310,though in other embodiments the controller 870 is powered by acombination of the battery 875 and the power generating device 320 orsolely by the power generating device 320.

The vehicle 890 also includes rear wheels 893 and front casters 895. Therear wheels 893 are engaged to and driven by the transaxle 310 (asdescribed above in conjunction with FIG. 3).

FIG. 14 illustrates a zero-turn vehicle 1090 that is similar in manyrespects to the vehicles described above, and in particular vehicle 990of FIG. 9. Vehicle 1090 includes transaxle 1310′ shown in FIG. 10A.Prime mover 1091 is supported by frame 1092, with prime mover 1091configured to drive the input shaft 314 of transaxle 1310′ to power thepower generating device 320 of the transaxle 1310′. Vehicle 1090includes a belt and pulley assembly 1097 that operably connects primemover 1091 to input shaft 314, and power generating device 320 includesa PTO clutch-brake assembly 350. It will be understood that prime mover1091 could be mounted above transaxle 1310′ in a direct drivearrangement.

Vehicle 1090 also includes two operator controls 384 a′, 384 b′ (shownhere as levers and position sensor modules) operatively connected toCAN-Bus 360 by means of conductors 385 a and 385 b to allow the vehicleuser to independently control the electric motors 330 a, 330 b oftransaxle 1310′. CAN-Bus 360 is also connected to VIM 355 by means ofconductor 323 as previously described, and is connected to motorcontrollers 349 a and 349 b by means of conductors 333 a′ and 333 b′.Battery 375 is also connected to VIM 355 by means of conductor 325 andto power generating device 320 by means of conductor 324.

Vehicle 1090 includes driven rear wheels 1093 and front casters 1095similar to the embodiments of FIGS. 6 and 9. Vehicle 1090 furtherincludes a mowing deck 1098 supported by frame 1092. Prime mover 1091powers one or more blades 1098 a of the mowing deck 1098 via engagementof the PTO clutch-brake 350 and by means of a belt and pulley assembly1099.

While specific embodiments of the invention have been described indetail, it will be appreciated by those skilled in the art that variousmodifications and alternatives to those details could be developed inlight of the overall teachings of the disclosure. Accordingly, theparticular arrangements disclosed are meant to be illustrative only andnot limiting as to the scope of the invention which is to be given thefull breadth of the appended claims and any equivalent thereof.

The invention claimed is:
 1. A vehicle drive and control system for useon a vehicle having a prime mover, and at least one driven wheel, thevehicle drive and control system comprising: an operator control device;a housing having a first side and a second side opposite the first side;a single axle extending out one of the first side or the second side ofthe housing; an input shaft extending into one of the first side or thesecond side of the housing, wherein the input shaft is parallel to thesingle axle and is engaged to and driven by the prime mover; a powergenerating device disposed within the housing and driven by the inputshaft; an electric motor disposed within the housing and directlyconnected to and powered by the power generating device, wherein thesingle axle is driven by the electric motor; a battery operativelyconnected to and powered by the power generating device and disposedexternal to the housing; a generator controller disposed in the housingand operatively connected to the power generating device, wherein thegenerator controller is configured to back-drive the power generatingdevice when certain predetermined conditions are met; and a motorcontroller disposed in the housing and operatively connected to theoperator control device and the electric motor such that the motorcontroller may control an output of the electric motor based on inputreceived via the operator control device, and wherein the motorcontroller is configured to operate the electric motor as a generatorunder certain operating conditions.
 2. The vehicle drive and controlsystem of claim 1, wherein the input shaft extends out the first side ofthe housing and the single axle extends out the second side of thehousing.
 3. The vehicle drive and control system of claim 1, wherein theinput shaft and the single axle both extend out the same side of thehousing.
 4. The vehicle drive and control system of claim 1, furthercomprising a motor output shaft driven by the electric motor, and areduction gear assembly disposed within the housing and engaged to anddriven by the motor output shaft, wherein the reduction gear assembly isengaged to and drives the single axle.
 5. The vehicle drive and controlsystem of claim 4, wherein the input shaft extends out the first side ofthe housing and the single axle extends out the second side of thehousing.
 6. The vehicle drive and control system of claim 4, wherein theinput shaft and the single axle both extend out the same side of thehousing.
 7. The vehicle drive and control system of claim 1, wherein thesingle axle is directly driven by the electric motor.
 8. The vehicledrive and control system of claim 7, wherein the input shaft extends outthe first side of the housing and the single axle extends out the secondside of the housing.
 9. The vehicle drive and control system of claim 7,wherein the input shaft and the single axle both extend out the sameside of the housing.
 10. The vehicle drive and control system of claim1, wherein the power generating device is a generator.
 11. A vehicledrive and control system for use on a vehicle having a prime mover, andat least one driven wheel, the vehicle drive and control systemcomprising: an operator control device; a housing having a first sideand a second side opposite the first side; an input shaft extending intoone of the first side or the second side of the housing, wherein theinput shaft is engaged to and driven by the prime mover; a powergenerating device disposed within the housing and driven by the inputshaft; a single axle at least partially disposed in the housing andparallel to the input shaft; a single electric motor disposed within thehousing and directly connected to and powered by the power generatingdevice, wherein the single axle is driven by the single electric motor;a battery operatively connected to and powered by the power generatingdevice and disposed external to the housing; a generator controllerdisposed in the housing and operatively connected to the powergenerating device, wherein the generator controller is configured toback-drive the power generating device when certain predeterminedconditions are met; and a motor controller disposed in the housing andoperatively connected to the operator control device and the singleelectric motor such that the motor controller may control an output ofthe single electric motor based on input received via the operatorcontrol device, and wherein the motor controller is configured tooperate the single electric motor as a generator under certain operatingconditions.
 12. The vehicle drive and control system of claim 11,wherein the single axle is a through shaft extending out both the firstside and the second side of the housing, and the single axle drives theat least one driven wheel.
 13. The vehicle drive and control system ofclaim 11, wherein the input shaft extends out the first side of thehousing and the single axle extends out the second side of the housing.14. The vehicle drive and control system of claim 11, further comprisinga motor output shaft driven by the single electric motor, and areduction gear assembly disposed within the housing and engaged to anddriven by the motor output shaft, wherein the reduction gear assembly isengaged to and drives the single axle.
 15. The vehicle drive and controlsystem of claim 14, wherein the input shaft extends out the first sideof the housing and the single axle extends out the second side of thehousing.
 16. The vehicle drive and control system of claim 14, whereinthe input shaft and the single axle both extend out the same side of thehousing.
 17. The vehicle drive and control system of claim 11, whereinthe input shaft and the single axle both extend out the same side of thehousing.